Sensitivity analysis of ECOSYS-87: An emphasis on the ingestion pathway as a function of radionuclide and type of deposition

Journal Article · Sun May 01 04:00:00 EDT 1994 · Health Physics

DOI:https://doi.org/10.1097/00004032-199405000-00003· OSTI ID:249940

Hinton, T G ^[1]

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1. Paul Scherrer Institute, Villigen (Switzerland)

A sensitivity analysis of parameters associated with the ingestion pathway was conducted for the computer model ECOSYS-87. The model is currently being used extensively throughout Europe for accident consequence analysis following a nuclear release. Individual parameter perturbation was used to develop sensitivity indices. The sensitivity indices identified parameters whose uncertainties had a large impact on model results. The relative ranking of the sensitive parameters depended on the radionuclide ({sup 137}Cs, {sup 90}Sr, {sup 131}I, or {sup 239}Pu), whether dose 1 y or 50 y postaccident was being considered, and whether the deposition event was dry or mixed. The most influential parameter for {sup 139}Pu was resuspension. Parameters to which human dose was sensitive following exposure to {sup 137}Cs, {sup 90}Sr, and {sup 131}I, were as follows: yield (biomass) of vegetation, transfer of radionuclides from plants to animals, deposition velocity, changes in radionuclide concentrations due to food processing, livestock feeding rates, and weathering of radionuclides from plant surfaces. The ranking of {sup 131}I`s parameters was governed by its 8-d physical half-life. Parameters that affected the initial deposition, parameters that could rapidly affect the transfer of {sup 131}I from the biota to humans, or parameters that allowed {sup 131}I to decay prior to consumption were important. Parameters specific to {sup 90}Sr and {sup 137}Cs included transfer of radionuclides from soil to plant, leaching from the plant rooting zone, and resuspension. Parameters associated with the movement of radionuclides within the soil were not as important for {sup 137}Cs as they were for {sup 90}Sr. Extending the model end point from 1 y to 50 y postaccident also caused a shift in the relative ranking of sensitive parameters for {sup 137}Cs and {sup 90}Sr. 29 refs., 3 figs., 5 tabs.

• Sponsoring Organization: USDOE
• OSTI ID: 249940
• Journal Information: Health Physics, Journal Name: Health Physics Journal Issue: 5 Vol. 66; ISSN HLTPAO; ISSN 0017-9078
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
56 BIOLOGY AND MEDICINE
APPLIED STUDIES
99 GENERAL AND MISCELLANEOUS
ANIMALS
BIOLOGICAL HALF-LIFE
CESIUM 137
CONTAMINATION
E CODES
ENVIRONMENTAL EFFECTS
ENVIRONMENTAL EXPOSURE PATHWAY
EUROPE
FOOD CHAINS
HUMAN POPULATIONS
INGESTION
IODINE 131
LEACHING
PLANTS
PLUTONIUM 239
RADIATION ACCIDENTS
RADIATION DOSES
RADIONUCLIDE MIGRATION
SENSITIVITY ANALYSIS
SOILS
STRONTIUM 90